The subject application relates to solid state storage devices and, in particular, solid state storage devices having backup power systems.
Solid state storage devices using flash memory provide performance and power consumption advantages over conventional hard drives. To further improve performance, many solid state storage devices are incorporating and using volatile memory, such as dynamic random access memory (DRAM) or static random access memory (SRAM), in addition to flash memory. For example, volatile memory may be used to cache data and/or temporarily store tables used to manage the data stored in flash memory. Unlike flash memory, however, volatile memory requires power to maintain the data stored therein. If power is interrupted, any data stored in volatile memory may be lost. This data loss may increase overhead operations in a solid state storage device by requiring lost tables to be reconstructed. Furthermore, this data loss may result in permanently losing cached data that had not been stored in flash memory prior to the power interruption. Furthermore, a power interruption may prevent a write operation to flash memory from completing resulting in lost or corrupt data in the flash memory.